I have data like this in a .dat format
1 13 0.54
1 15 0.65
1 67 0.55
2 355 0.54
2 456 0.29
3 432 0.55
3 542 0.333
I want to merge the rows starting with 1, 2 and so on and want a final file like this:
1 13 0.54 15 0.65 67 0.55
2 355 0.54 456 0.29
3 432 0.55 542 0.333
Can someone please help me? I am new to Python. Unless I get this format file I cannot run my abaqus code.
Explanation - first we split the file into lines, and then we split the lines on white space.
We then use itertools.groupby to group the lines by their first element.
We then take the values, ignore the first element and join on spaces, and prepend the key that we were grouping by and a space.
from itertools import groupby
with open("file.dat") as f:
lines = [line.split() for line in f.readlines()]
filteredlines = [line for line in lines if len(line)]
for k, v in groupby(filteredlines, lambda x: x[0]):
print k + " " + " ".join([" ".join(velem[1:]) for velem in v])
print
The Python CSV library can be used to both read your DAT file and also create your CSV file as follows:
import csv, itertools
with open("input.dat", "r") as f_input, open("output.csv", "wb") as f_output:
csv_input = csv.reader(f_input, delimiter=" ", skipinitialspace=True)
csv_output = csv.writer(f_output, delimiter=" ")
dat = [line for line in csv_input if len(line)]
for k, g in itertools.groupby(dat, lambda x: x[0]):
csv_output.writerow([k] + list(itertools.chain.from_iterable([value[1:] for value in g])))
It produces an output file as follows:
1 13 0.54 15 0.65 67 0.55
2 355 0.54 456 0.29
3 432 0.55 542 0.333
Tested using Python 2.7
setdefaultordefaultdictdocs.